X = int(input())

if X >= 30:
    print('Yes')
    
if X < 30:
    print('No') X = int(input()) X int(input()) int input() input if X >= 30:
    print('Yes')
     X >= 30 X 30 print('Yes') print 'Yes' if X < 30:
    print('No') X < 30 X 30 print('No') print 'No' X = int(input()) int(input()) X
X = int(input())

if X >= 30:
    print('Yes')
    
if X < 30:
    print('No')